This patch comes from upstream:
https://gitlab.freedesktop.org/farstream/farstream/-/merge_requests/4

From 54987d445ea714b467d901b7daf8c09ed0644189 Mon Sep 17 00:00:00 2001
From: Debarshi Ray <debarshir@freedesktop.org>
Date: Thu, 12 Mar 2020 14:07:23 +0100
Subject: [PATCH] build: Adapt to backwards incompatible change in GNU Make 4.3

GNU Make 4.3 has a backwards incompatible change affecting the use of
number signs or hashes (ie., #) inside function invocations. See:
https://lists.gnu.org/archive/html/info-gnu/2020-01/msg00004.html

In this case, it would expand the '\#' in the '\n\#include \"$(h)\"'
argument to the foreach call to '\#', not '#'. This would lead to
spurious backslashes in front of the '#include' directives in the
generated fs-enumtypes.c file.

Spotted by Ernestas Kulik.
---
 common-modified/gst-glib-gen.mak | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/common-modified/gst-glib-gen.mak b/common-modified/gst-glib-gen.mak
index 14f1ba37..2247a41c 100644
--- a/common-modified/gst-glib-gen.mak
+++ b/common-modified/gst-glib-gen.mak
@@ -6,7 +6,8 @@
 #glib_gen_prefix=gst_color_balance
 #glib_gen_basename=colorbalance
 
-enum_headers=$(foreach h,$(glib_enum_headers),\n\#include \"$(h)\")
+hash:=\#
+enum_headers=$(foreach h,$(glib_enum_headers),\n$(hash)include \"$(h)\")
 
 # these are all the rules generating the relevant files
 $(glib_gen_basename)-enumtypes.h: $(glib_enum_headers)
-- 
GitLab

s.scm?id=9a86e2e97fd91003ee089dc0fed35d848e84d0f1'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/tests/processes.scm'>
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<div class='path'>path: <a href='/guix/log/?id=9a86e2e97fd91003ee089dc0fed35d848e84d0f1'>root</a>/<a href='/guix/log/tests?id=9a86e2e97fd91003ee089dc0fed35d848e84d0f1'>tests</a>/<a href='/guix/log/tests/processes.scm?id=9a86e2e97fd91003ee089dc0fed35d848e84d0f1'>processes.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/processes.scm?id=9a86e2e97fd91003ee089dc0fed35d848e84d0f1&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2019-12-10 10:49:42 +0100'>2019-12-10</span></td><td><a href='/guix/commit/tests/processes.scm?id=0b5ad0e756a34d5e3ed1f37c3d4083a330fa33f5'>tests: processes: Skip tests if running with binfmt.</a><span class='msg-avail'>...<span class='msg-tooltip'>* tests/processes.scm (binfmt-misc?): New procedure,
(test-assert*): new procedure that skips the test if binfmt-misc? returns
</span></span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2018-10-29 00:13:38 +0100'>2018-10-29</span></td><td><a href='/guix/commit/tests/processes.scm?id=63eb2b899be7ac857454442e09d0ebd23fe4f871'>Add 'guix processes'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/scripts/processes.scm, tests/processes.scm: New files.
* Makefile.am (MODULES): Add the former.
(SCM_TESTS): Add the latter.
* po/guix/POTFILES.in: Add guix/scripts/processes.scm.
* doc/guix.texi (Invoking guix processes): New node.
(Invoking guix-daemon): Reference it.
</span></span></td><td>Ludovic Courtès</td></tr>